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-rw-r--r--src/devices/cpu/pace/pace.cpp10
1 files changed, 6 insertions, 4 deletions
diff --git a/src/devices/cpu/pace/pace.cpp b/src/devices/cpu/pace/pace.cpp
index bc0e6f5b62a..03b36312930 100644
--- a/src/devices/cpu/pace/pace.cpp
+++ b/src/devices/cpu/pace/pace.cpp
@@ -6,10 +6,12 @@
The IPC-16A PACE (Processing and Control Element) was one of the first
commercially available 16-bit microprocessors. It was a successor to
- the multiple-chip IMP-16 processor and implemented a similar four-
- accumulator architecture in a single PMOS LSI package using internal
- microcode. PACE requires two clock inputs with non-overlapping low
- phases and frequencies between 1.25 and 1.538 MHz.
+ the multiple-chip IMP-16 processor (itself loosely based on the Data
+ General Nova) and implemented a similar four-accumulator architecture
+ in a single PMOS LSI package using internal microcode. The two clock
+ inputs with non-overlapping low phases required by PACE may be
+ generated by the DP8302 STE (System Timing Element), which divides its
+ oscillator input by 2.
The standard machine cycle takes 4 clock periods (and the shortest
instructions take 4 cycles each), though cycles can be stretched by